Diverse screens with cleaning and distribution means



May 12, 1970 R. K. M KlBBEN E 3,511,373

DIVERSE SCREENS WITH CLEANING AND DISTRIBUTION MEANS Filed May 22, 19676 Sheets-Sheet 1 [/6 /4Zfi K M 0556 77/500065 K 106576444 INVENTORS.

May 12, 1970 R. K. MCKIBBEN ET AL DIVERSE SCREENS WITH CLEANING ANDDISTRIBUTION MEANS Filed May 22, 19s a Sheeis-Sheet 2 May 12, 1970 R. K.M KIBBEN E 3,511,373

DIVERSE SCREENS WITH CLEANING AND DISTRIBUTION M EANS Filed May 22. 1967'6 Sheets-Sheet 4 w 96 i /24 w w E67 7 2/0 /40 z/wz/aef/v 79600026 5W657F4 mam/v6. PZSA/EAA 4 INVENTOR5.

May12 ,1970 MCKB Q ETAL A 3,511,313

DIVERSE SCREENS WITH CLEANING AND DISTRIBUTION MEANS Filed May 22, 1967e Sheets-Sheet 5 Arraz/vfx May 12, 1970 M KIBBEN ET AL 3,511,373

DIVERSE SCREENS WITH CLEANING AND DISTRIBUTION MEANS Filed May 22, 19676 Sheets-Sheet 6 Q5 Qw 77/600026 z WfSTFAAA @424 ram 5. P'SNfLINVENTORS.

United States Patent Us. (:1. 209-234 9 Claims ABSTRACT OF THEDISCLOSURE A screening separator including a first planar vibratingscreen positioned in a vibratory housing structure and a pair ofconcentric rotating cylindrical screens p0- sitioned above the planarscreen and detached from the vibratory housing structure, and means forfeeding a liquid slurry to the innermost of the cylindrical rotatingscreens, and means for conducting material rejected by the cylindricalscreens to the planar screen, and means for separately dischargingmaterial passing through the screens and material rejected by thescreens, each of the cylindrical screens having inoperative positionsand means for cleaning the cylindrical screens through the inoperativepositions while the screens are rotating.

This invention relates to screening separators and more particularly toan improved separator employing a horizontal vibrating screen which isuseful in the separation of relatively small amounts of solids from alarge volume of liquids.

Horizontal screen vibratory separating devices such as the typedisclosed, for example, in U.S. Pats. 3,035,- 700; 3,156,643; 3,029,946;2,777,578; 2,753,999; 2,714,- 961; 2,696,302; 2,676,706; and 2,284,671,have gained wide acceptance in the separation of solids and in theseparation of small quantities of solids from a large quantity ofliquid. However, there have been certain applications in which thecapacity of such separators has limited their applicability.

For example, when using the conventional vibrating screen separator toremove a relatively small amount of solids from a large volume ofliquid, .the capacity of the separator is materially retarded by thelimited surface area of the horizontal screen because there is a finiterate at which the liquid will pass through the screen, particularly inthe presence of the solids, which tend to concentrate on the screensurface. In such instance, the capacity of the separator to remove therelatively small amount of solids is limited by the ability to move thesolids across the screen and agglomerate the solids with largerparticles so that a maximum open screen area is available to the liquid.Further, when using the vibrating screen separator to remove arelatively small amount of solids from a large volume 'of liquid,particularly where solids are finely divided or are semi-solids, thescreen cloth also has a tendency to become bridged or clogged by theparticulate or semi-solid material. This is particularly true in makinga preliminary separation between water and finely divided solids in rawsewage where the sewage contains suspended grease often found indomestic household wastes. In these instances, the semi-solid greasetends to bridge and adhere to the screen cloth and gradually reduces thecapacity of the cloth to discharge water.

I It is therefore, an object of this invention to provide an improvedvibratory separator which employs a horizontal screen.

'ice

It is another object of this invention to provide an improved vibratoryseparator, which separator employs a etached circular screen and whichis particularly adapted to the separation of large quantities of liquidmaterial from a relatively small quantity of solid material.

It is a still further object of this invention to provide a separatorhaving a novel arrangement which enables the separator to operate atincreased capacities by increasing the screen area available with agiven diameter unit.

Yet another object of the invention is to provide a separator unit whichcan be cleaned either while in operation or during short pauses in theoperation without the necessity of dismantling the unit or removing thescreen therefrom.

A further object of the invention is to provide a vibratory screeningapparatus useful in the separation of liquidsolid mixtures.

A still further object of this invention is to provide an improvedseparator device.

The above and other objects of the present invention are, in part,accomplished by a device which comprises a novel arrangement of screens;by which arrangement more screen surface area is provided, and a processand device for improving a separation in a screening apparatus byoperating the device for its intended purpose and preventing screenclogging by applying fluid to an area of the screen cloth in thedirection opposite the normal flow of liquid.

The vibratory separator of this invention generally comprises a mainhousing structure; a second housing structure therein, a first planarscreen having an outer periphery secured to the second housingstructure, a second screen; means for delivering material to beseparated to the second screen adjacent its surface; the second screenbeing positioned above the first screen such that no portion of thesecond screen is in a plane parallel to the first screen and such thatany of the material which does not flow through the second screen isdelivered to the first screen at near the periphery thereof, said secondscreen detached from said second housing; means for vibrating the secondhousing structure and the first screen to cause movement of the materialon the first screen, and means to cause movement of the second screen.In addition to the basic vibratory separator with the second detachednon-planar, non-parallel screen, the present invention in one of itsaspects, makes use of a novel arrangement for cleaning the screenseither while in operation or intermittently between periods ofoperation.

In a preferred embodiment of the invention, the second screen is acylindrical screen positioned so that the axis of the cylinder formed bythe screen is perpendicular to the center of the first screen. However,any screen configuration in which the second screen is neither parallelto nor in the same plane as the first screen is within the purview ofthe invention so long as the discharge (i.e., material not passingthrough) of the second screen is the feed to the first screen. Thecylindrical screen is preferred because it lends itself to inclusion ina cylindrical housing or frame and provides a maximum surface area perunit of height above the planar screen.

In another preferred embodiment of the invention, the second screen is acylindrical screen positioned above the horizontal screen and there isyet a third screen which is cylindrical and of smaller diameterpositioned concentrically within the second screen. In this preferredembodiment of the invention, both the second and third screens rotateand the third screen serves to protect the second screen from damage bylarge particles of oversize material. Fluid is fed to the cylindricalscreen and passes through the third screen from a distributor dome withflow dividers. The material passing through the third screen isdistributed on a second flow divider and distributor pan from whence itis impinged on the second screen. Oversize material from both the secondand third screen is fed to the first screen. In each of the second andthird screens there are units of area through which the fluid does notflow so that the screen can be constantly backwashed while in operationby spray nozzles impinging fluid against the exterior portions of theinoperative section of each screen as will be further described indetail hereinbelow.

In the drawings accompanying this application, FIG. 1 is an overallfront view from the exterior of a housing structure which can be used tohouse the separator of this invention;

FIG. 2 is a vertical cross-section of the interior of the structureshown in FIG. 1;

FIG. 3 is a plan view looking downward on the top through the line 3-3of FIG. 2;

FIG. 4 is an enlarged fragmentary cross-section of the upper portion ofFIG. 2;

FIG. 5 is an enlarged fragmentary cross-section of a portion of FIG. 4showing the screen rotating mechanism in detail;

FIG. 6 is a cross-section taken through the line 66 of FIG. 2;

FIG. 7 is a partial perspective of the cylindrical rotating screen,distributor plan and flow divider in partial cuty;

FIG. 8 is an enlarged perspective of the flow divider and fluiddistribution means employed in the invention;

FIG. 9 is an enlarged plan view in fragment of a portion of the flowdivider arrangement;

FIG. 10 is an enlarged fragmentary cross-section of a screen tensioningarrangement; and

FIG. 11 is a section through the line 11-11 of FIG. 10.

Referring now to the drawings, the vibratory shaking or screeningdevice, as shown in FIG. 2, consists of a base frame 10 on the upperportion of which is mounted a ring of springs 11 which supports thevibratory screening device and isolates the vibrations imparted uponsuch device from the base frame 10.

A vibratory unit comprising a motor 12 and upper and lower eccentricweights 13 and 14 respectively, is mounted by means of the mountingbrackets 15 to a cylindrical extension 16 of the upper base 17 which issupported on the ring of springs 11 and is reinforced by gusset plates18 which project between the springs 11.

The relationship of the vibratory unit and the base frame 10, asdescribed above, may be varied by other arrangements. For example, amotor may be mounted upon the base frame 10. A belt drive from suchmotor extends to and rotates the eccentric weights which are mounted onthe upper base 17.

On the upper base frame 17 is mounted a cylindrical spacing frame 19having a discharge duct 20 projecting therefrom and communicating with acylindrical opening 21 in the approximate center through the collectorpan 22.

Secured to the interior of the spacing frame 19 is a sloping receivingpan 23 which is inclined and which is isolated from the interior of thedischarge duct 20 by the walls of the opening 21. The pan 23 slopesupwardly from the lower portion of the frame 19 and communicates withthe walls of the opening 21. At the bottom of the frame 19 is a clampring 24 which secures the lower edge of the frame 19 to the upper base17.

On the cylindrical spacing frame 19 is mounted a cylindrical screentension spacing frame 25, the lower edge of which is secured to thespacing frame 19 by the clamp ring 26.

Affixed by welding or other suitable means to the interior wall of theframe at spaced intervals about the periphery of the frame 25 arehorizontally positioned hollow struts or pipes 27 which radiate inwardlyfrom the periphery of the frame 25 toward the center. The inwardlyradiating hollow struts 27 communicate with the hollow support ring orcircular pipe 28 and are affixed thereto by welding, threaded couplingor other suitable means. Brackets 29 are affixed by welding or othersuitable means to the ring 28 at spaced intervals about the ring 28.Vertically positioned air cylinders 30 are affixed by bolting, weldingor other suitable means to the provided brackets 29 which support theair cylinders 30. Afiixed to the lower portion of each air cylinder 30in a U-shaped air line 31, which communicates with the hallow ring 28Theradiating struts 27 and circular ring 28 function as a support and alsoas a means to pass air to the air cylinders 30. Air line fitting 32 inthe cylindrical frame 25 communicates with one of the hollow struts 27.Therefore, the piston 33 of the air cylinder 30 may be actuated bypassing air from the fitting 32 into the hollow struts 27, the air thenpassing into the circular ring 28 and being distributed into the airlines 31 spaced at intervals around the ring 28 and which communicatewith the air cylinder 30.

Although the strut 27 and ring 28 as above described are employed tofunction as air lines to the respective air cylinders 30, it should beobserved that as an alternative arrangement an internal air line (notshown) may pass through one or more of the struts 27 and ring 28,ultimately communicating with each air cylinder 30 by an air linesimilar to 31.

Because only a single air line 31 is atfixed to the lower portion of theair cylinder 30 as shown in FIG. 2 the cylinder 30 is capable ofactuating the piston 33 only upward relying on gravity for any return ordownward movement of the piston 33. It should, however, be observed thata double actuating cylinder may be employed where, by virtue of an airline at the lower and upper portion of the cylinder, the piston may beactuated upward or downward in a manner which is commonly known in theart. Further, the cylinder 30 need not necessarily be air actuated, butmay also be liquid actuated.

Affixed by welding or other suitable means to the underside of theperipheral flange 34 of the conical funnel 35 is a toggle pad 36. Thetoggle pad 36 is attached to the piston 33 and thus the funnel 35 isswivelly mounted at spaced intervals about the periphery of the flange34 to the pistons 33 which project from their respective air cylinders30.

As shown in FIG. 2, the inner periphery and outer periphery of thehorizontal screen 37 are secured to inner and outer tension rings 179and 38 respectively, thus forming a rigid single unit. The innerperiphery of the screen 37 is aflixed to the inner tension ring 179 byspot welding, bonding or other suitable means. The outer periphery ofthe horizontal screen 37 rests upon the outer marginal tension ring 38and is bonded, spot welded or otherwise aflixed thereto. Upon affixingthe peripheries of the screen 37 to the tension rings 179 and 38, thescreen 37 and tension rings form a single rigid and removable unit. Thescreen assembly is placed onto the vibratory separator unit so that theinner tension ring merely rests upon the outwardly projecting peripheralflange 34 of the conical funnel 35 which, as previously described, isswivelly mounted upon the pistons 33 by virtue of the toggle pads 36.

A circular ring 45 of rubber, polyurethane or other suitable materialwhich is affixed in a suitable manner to the upperside of the peripheralflange 34 reduces the abrasive action between the tension ring 179 andflange 34 which would exist during the vibratory operation of theseparator unit.

A lip projects outwardly from the outer margin of the tension ring 38,the lip being interposed between the spacing frames 25 and 39 andresting upon the flange which projects outwardly from the upperperiphery of the spacing frame 25. A clamp ring 40 secures the spacingframes 25 and 39 and the interposed flange of the tension ring 38.

The fluid flowing in the lines to accomplish the cleaning need not besteam but may be any suitable solvent which will melt or dissolve thematerial which causes the screen clogging or bridging. Thus, undercertain circumstances, hot water may be employed to eif ct the desiredsteam cleaning.

The steam cleaning apparatus is pre-assembled into the device, but ismechanicallyseparated therefrom so that no vibration is imparted to thesteam cleaning apparatus.

Prior to operation of the vibratory separator and by virtue of thescreen tension arrangement as previously described, the pistons 33 ofthe air cylinders 30' are vertically actuated to a predetermined heightso as to raise the funnel 35 and overlying inner screen tension ring 179to a height which sufliciently tensions the shakingscreen 37 to preventscreen flopping during operation of the vibratory separator.

The separator as thus far described functions to separate materials oftwo diiferent sizes (or liquid from sblid) through the screen 37, byvirtue of the vibratory motion imparted by the vibratory unit, includingupper and lower eccentric weights 13 and 14 and the f ed arrangement bywhich the material to be separated is fed onto the outer periphery ofthe screen 37. As the material to be separated is fed onto the screen37, the imparted vibratory motion causes the material to move along thescreen, the oversize portion of the material being discharged throughthe discharge opening 21.

The undersize material which passes through the screen 37 falls onto thereceiving pan 22 and, by falling along the receiving pan 22 and aroundthe inside of the frame 19, is ultimately discharged through thedischarge duct 157.

To remove the screen 37, the clamp ring 40 is loosened from its clampingposition and the spacing frame 39 is removed from the separator unit.The screen 37 may then be easily lifted from the separator.

Avertical inlet pipe 41 passes through the central opening in thedome-shaped top 42 of the cylindrical shell 43. The peripheral flange167, welded or otherwise aflixed about the wall of the pipe 41, is scured to the domeshaped top 42 by bolts 44 which pass through theperipheral edge of the opening in the top 42 and the flange 167. As bestshown in FIGS. 4 and 5, disposed near the lower periphery of the pipe 41on a plane perpendicular to the vertical pipe is the circular bearingsupport 45 which is welded or otherwise suitably aifixed about the wallof the pipe 41. The outer peripheral edge of the circular bearingsupport 45 is provided with a bevel 46 upon which rest a plurality ofspherical bearings 47. The circular L-shaped flange 48 comprising anupper and lower horizontal member interconnected by the vertical flange,abuts the periphery of the support 45 so as to enclose the ball bearingwithin the confines of the bevel 46. and the upper horizontal andvertical portion of the L-shaped flange 48. The lower horizontal memberof the flange 48 rests upon the circular lower bearing support 172. Anannular bearing of polyurethane or other suitable material is interposedbetween the lower peripheral edge of the bearing support 45 and thelower bearing support 172. The lower bearing support 172 rests upon theinner periphery of a support dome 51. Positioned on the lower horizontalmember of the L-shaped flange 48 is an annular screen rotating sprocket50. The sprocket 50, horizontal member of the flange 48, lower bearingsupport 172 and inner periphery of the support dome are rigidly securedtogether by virtue of a bolt 170 passing through such members, the endof the bolt being provided with an internally threaded nut 171.

By virtue of the vertical and horizontal members of the flange 48resting against the plurality of bearings in the bevel 46 and the innerprojecting portion of the lower bearing support resting against lowerannular bearing 49, the sprocket 50, L-shaped flange 48, lower support172 and support dome 51 may rotate about the stationary bearing support45 and inlet pipe 41.

As best shown in FIGS. 3, 4 and 5, hollow sleeves 52, located atintervals about the dome 51, vertically project through the rotatingscreen support dome, the upper portion of such sleeve being welded orotherwise suitably secured to the dome 51. A bolt 53 passes through thesleeve 52 and the horizontal portion 54 of a screen mount ring 55, suchring resting against the lower peripheral edge of the sleeve 52. Upontightening the internally threaded nut 169 upon the end of the bolt 53,the horizontal portion 54 of the mounting ring 55 is secured aginst thelower peripheral edge of the sleeve. The upper periphery of thecylindrical screen 56 is welded, bonded or otherwise suitably afiixed tothe vertical portion 57 of the ring 55. The lower periphery of thescreen 56 is bonded, welded or otherwise suitably secured to thevertical portion of a lower mounting ring 58.

As shown in FIGS. 3 and 4, positioned at intervals about the peripheraledge 59 of the rotating dome 51 and vertically projecting upwardtherefrom, is a T-shaped flange 60.

In FIGS. 4 and 10, the externally threaded bolt 63 projects downwardlythrough the provided opening in the outwardly projecting horizontalportion 62 of the flange 60. The upper end of the bolt 63 projectingabove the outer portion 62 of the flange 60 is fitted with an internallythreaded nut 64.

As best shown in FIG. 10, the internally threaded nut 64 is attached tothe lowermost end of the bolt 63, such nut, in turn, being welded orotherwise suitably secured to the horizontal flange of the uppercircular screen support ring 66. The lower periphery of the verticalportion 67 of the ring 66 is provided with a U-bend portron 68. Theupper periphery of the fine screen 70 is welded, bonded or otherwisesuitably secured to the outer vertical side of the U-shaped mountingring 69. Although the mounting ring 69 may be constructed from metal, itis preferable that the mounting ring 69 be made of a resilient materialsuch as polyurethane.

The U-shaped mounting ring 69 is interconnected with theU-shaped portion68 of the support ring 66. The lower periphery of the screen 70 isbonded, welded or otherw1se suitably secured to the lower mounting ring74. The lower U-shaped mounting ring 74 is interconnected with theU-shaped portion 73 of the vertical flange 72 of the lower support ring71. Extending between the hor zontal flange of the upper support ring 66and the horizontal flange of the lower support ring 71 is thespring-loaded tensioning rod 75. The spring-loaded ten- SlOIllIlg rodcomprises the elongated hollow cylindrical shell 76 within the lowerportion of which is welded the rod 79. A nipple 82 projects downwardfrom the lowermost portion of the rod 79. I Positioned within the upperportion of the shell 76 is the slidable rod 78. The spring 77 extendsbetween the upper end of the stationary rod 79 and the lower end of theslidable rod 78. The horizontal rod 80 passes through the slidable rod78 with the projecting ends of the rod 80 extending through verticalchannels 81 provided on opposite sides of the shell 76. A nipple 82projects from the uppermost end of the slidable rod 78. The tensioningrod device 76 is inserted in its extending position between the upperand lower support ring 66 and 71 whereby the nipple projecting from thestationary rod 79 is inserted in an opening 174 provided in the lowersupport ring.

The projecting nipple 82 of the slidable rod 78 is inserted into theprovided opening in upper support ring 66.

Inorder to assemble and disassemble the rotating cylindrical screenassembly, including the outer rotating screen 70 and the inner rotatingscreen 56, the outer screen 70 and supporting rings 66 and 71 may beraised manually and the nut 64a rotated downwardly on the bolt 63. Thisprovides access to the feed pipe 136 and quick disconnect; coupling 137.

As best shown in FIGS. 10 and 11, the cylindrical screen 70 is assembledand removed from the unit by virture of the spring loaded tensioning rod75. The screen 70 has upper and lower mount rings 69 and 74 of aU-shaped resilient channel material which fit over the inverted U-shapedportions 68 and 73. When the tension rods 75 are removed, the channelmembers, with the screen attached, are placed over the U-shaped members68 and 73 and the tension rods are placed into the holes providedtherefor by depressing the spring handle 80. The lower support ring 71is otherwise detached completely from the remainder of the device.

As best shown in FIG. 4, the rectangular motor support plate 84 isbolted, welded or otherwise secured to the periphery of the upperportion of the circular bearing support and such plate extendingradially therefrom and being disposed over the rotating screen supportdome 51. Welded, bolted or otherwise aflixed to the upper portion of thesupport plate 84 is the upper motor support plate 87 which furtherreinforces the lower support plate 84. Gusset plates 85 and 86, weldedor otherwise suitably secured to the bearing support 45 and motorsupport plate 84, provides additional stability to the plate 84.

The vertically positioned motor 88 is bolted or otherwise affixed to theupper and lower support plates 84 and 87. The rotating shaft 90 of themotor 88 extends vertically downward through provided openings in thesupport plates 87 and 84. The screen drive socket 89 is suitably securedto the lowermost end of the shaft 90 in such a manner as to dispose thescreen drive sprocket 89 at the same plane as the screen rotatingsprocket 50 (FIG.

It should be observed that the motor 88 may be air or electricallyactuated.

The screen drive sprocket 89 is associated with and rotates the screenrotating sprocket through the drive chain 91. As an alternative, themotor may rotate the screen drive sprocket through a belt-drivearrangement instead of the chain 91 connecting the screen rotatingsprocket 50 (FIG. 5) with the drive sprocket 89.

As best shown in FIG. 4, an elongated bolt 93 passes through theopenings in the bearing support 45 provided at spaced intervals aboutthe inner periphery of the support 45. A hollow spacing sleeve 92 fitsover the downward extending portion of the bolt 93. The lowermostportion of the bolt 93 which extends beyond the lowermost end of thesleeve 92, passes through opening 95 provided on the horizontal flange94 (FIG. 8) the end of such bolt being provided with an internallythreaded nut which, upon tightening, secures the flange 94 against thesleeve 92.

The flange 94 is welded or otherwise secured to the walls 97 of the flowdividers 96 which are positioned at spaced intervals about and welded orotherwise secured to the inner distributing pan 99. The innerdistributor pan 1s cylindrical with a dome-shaped top. The lower edgesof the walls 97 of the flow dividers 96 and the end 98 of the flowdividers, are contoured to the slope of the pan 99. The flow divider 96is positioned upon the pan 99 such that the walls 97 of the flow divider96 are aligned with an imaginary line from the center of the pan 99.

In FIG. 4, a horizontal flange 101 inwardly projects from the lowerperipheral edge of the inner distributing pan 99. The upper peripheralflange 102 of the conical solids deflector pan 100 is secured to theperipheral flange 101 of the pan 96 by bolts 103 which pass through theprovided openings about the flange 101 and 102 with the end of suchbolts secured to an internally threaded nut 104. The lower peripheraledge of the deflector pan is disposed above the vibrating screen 37 nearthe outer periphery thereof.

In FIG. 4, gusset plates 105, welded or otherwise aflixed to the conicaldeflector at spaced intervals, upwardly project from the conicaldeflector 100. The gusset plates 105 are welded or otherwise aflixed toand support the outer distributing dome 106.

In FIGS. 7 and 8, the flow dividers 109 are disposed at spaced intervalsabout the dome 106. The flow divider consists of side walls 110 whichconverge as they approach the inner periphery of the dome 106. The loweredge of the walls 110 conform to the shape of the dome and are weldedthereto. An apexed top member 111 is secured to or formed as afabricated extension of the upper edge of the walls 97.

The flow dividers 109, disposed on the outer distributing dome 106, areradially aligned with the flow dividers 96 disposed on the innerdistributing dome 99.

As shown in FIGS. 7 and 8, a helical surface 108 ascends from a point atthe outer periphery of the dome 106 and adjacent the wall of the flowdivider 109 to approximately half the height of the wall 97 of the nextadjacent flow divider 109.

The inner edge 175 of the helical surface 108 is welded, bonded orotherwise secured to the domed surface 107. The edge 176 of the helicalsurface 108 is welded or otherwise affixed to the wall 110 of the flowdividers 109.

As shown in FIG. 2, a vertical pipe 112 downwardly extends from thecoupling 120. The pipe 112 is parallel to and adjacent the outer surfaceof the screen 70. The lower portion of pipe 112 adjacent the verticalheight of the screen 75 is provided with a series of interconnectedstuds and spray nozzles. The horizontal pipes 115 extend from thecoupling to the coupling 119. The pipe 116 downwardly extends throughthe provided opening 117, FIGS. 2 and 3, in the bearing support 45 andthe opening 118 (FIGS. 2 and 6) in the inner dome-shaped distributor pan99. The lower end of the pipe 116 communicates with the horizontal pipe122 through the coupling 121.

The horizontal pipes 122 communicate with the vertical pipes 124 throughthe coupling 123. The upwardly extending vertical pipes 124 pass throughand are welded to the provided openings 177 (FIG. 4) spaced at intervalsabout the periphery of the deflector cone 100 and further extendupwardly through the provided openings 125 (FIGS. 4, 6, and 8) in theouter distributor dome 106, the upper portion of the pipes 124 beingdisposed parallel to and adjacent the outer surface of the inner screen56. The upper portion of the pipes 124, which are parallel to andadjacent the screen 56, are interconnected with studs 127 and spraynozzles 126 which direct the spray upon the surface of the screen 56.

The inner and outer screen cleaning arrangement, as above described, isa stationary unit.

A spray arrangement may also be employed to clean the horizontal screen37.

In FIG. 2, the horizontal entry line 128 communicates with the verticalpipe 129 through the coupling 132. The vertical pipe 129, disposedparallel to and adjacent the inlet pipe 41, downwardly extends throughthe provided opening 130 in the motor plate 84, the opening 117 in thebearing support 45, and the opening 131 in the dome-shaped member of theinner distributing dome 99.

The vertical pipe 129 communicates with the horizontal pipe 134 throughthe coupling 133. The vertical pipe 136 is supported by and communicateswith the horizontal pipe 134 by virtue of a rotable coupling 135 whichpermits the vertical pipe 136 to rotate. As shown in FIG. 1, thevertical pipe 136 downwardly extends through the central dischargeopening of the horizontal screen.

The vertical pipe 136 communicates with radiating arms i139 through theT-shaped coupling 138. Legs 140 vertically extend upward from the upperportion of the arms 139, at spaced intervals along the arms 139. Theupper end of each leg 140 is provided with the spray nozzle 141 whichdirects the fluid upon the undersurface of the screen 37. The nozzles141 may be canted to enable the cleaning arrangement including the pipe136, arms 139 and legs 140 to rotate in the coupling '135 by virtue ofthe reaction pressure of the fluid being emitted from the canted nozzles141.

The apparatus as above described functions to separate solids ofdifferent sizes and separate solids from liquids.

Material to be separated, such as for example, the suspended solids ofsewage eflluent, enters through the vertical inlet pipe 41. The eflluentdirection'flow is changed from vertical to horizontal by the innerdistributing dome 99 which is disposed beneath the inlet pipe 41. Thevelocity of eflluent flowing from the inlet pipe 41 onto the dome 99 maybe controlled by varying the distance between the lower periphery of theinlet pipe and the dome 99. This could be accomplished, for example, byplacing a slidable inner inlet pipe (not shown) within the inlet pipe41. As best shown in FIGS. 1 and 9, the distributing dome 99 directs theeffluent against the inner coarse mesh screen 56 as indicated by thearrow 148 (FIG. 9).

As previously described, the inner coarse screen 56 and outer fine meshscreen 70 revolve together at any desired rotational speed. To preventthe screen 56 from becoming clogged by the eflluent being directedagainst the screen, the stationary spray nozzles emit fluid upon thesurface of the screen 56. The flow divides 96 prevent the distributedeffluent from being distributed against the vertical portion of thescreen 56 that is being backsprayed by the spray nozzles \116.Therefore, as the screen 56 revolves, the entire surface of the screen56 ultimately is cleaned upon revolving past the vertically alignedspray nozzles 126.

The coarse material which does not pass through the inner revolvingscreen 56, falls onto the coarse solids deflector 100, which is disposedbelow the inner screen 56. The coarse material then travels down theslope of the conical deflector to become distributed from the peripheryof the deflector 100 onto the periphery of the vibratory screen 37.

As best shown in FIG. 7, the effluent which passes through the coarsemesh screen 56 is distributed into the outer distributing dome 106 whichdirects the effluent against the revolving fine mesh screen 70.

By virtue of the helical surface 108 of the dome 106, the effluent isdirected as a diagonal flow of eflluent against the screen 70. Bydirecting the eflluent against substantially the entire vertical heightof the screen 70, the screen wear is materially reduced. As the screen70 revolves about the helical surfaces 108 of the dome 106,substantially the entire vertical height of the screen 70 is subjectedto the effluent flow resulting in an even wear rate over the entirescreen 70. Further, by directing the effluent against a greater amountof screen area, the capacity of the separator is materially increased.

It should be observed that the incline of the helical surface ispreferably in the direction of the rotation of the screen 70.

It should further be recognized that any surface arrangement of the dome106 may be employed which would direct the efiluent againstsubstantially the entire vertical height of the screen surface.

The oversize material which does not pass through the fine mesh screen70, falls onto the outer periphery of the vibrating screen 37 of thevibratory screen apparatus. It should be observed that a flange 150inwardly projecting from the bottom periphery of the lower screensupport ring 71 prevents the oversize material from passing through thespace between the upper periphery of the 10 spacing frame 39 and thelower screen support ring 71 (FIG. 10).

As previously described, the material 'which does not pass through thecoarse mesh screen 56 or the fine mesh screen 70 becomes distributedonto outer periphery of the vibrating screen 37.

The vibratory separator functions to separate materials of two differentsizes (or liquid from solid) through the screen 37, by virtue of thevibratory motion imparted by the vibratory unit, including upper andlower eccentric weights 13 and 14. The vibratory motion causes thematerial to move along the screen 37; the oversize portion of thematerial falling into the discharge opening 21, traveling down thesloping pan 23 and becoming discharged from the discharge duct 20.

In order to prevent oversize material which is passing through theconical member 35 into the oversize discharge duct 20 from splashing outonto the oversize collector pan 22, the rotating arms 139 may beprovided with a splash guard 180. This splash guard 180 has slightlylarger diameter than the lowermost portion of the conical member 35 butcontinues the same general conical shape to direct material through thehole 21.

Undersize material passing through the screen 37 falls onto thedome-shaped receiving pan 22 and becomes discharged through thedischarge duct 157.

As above described, the oversize material not passing through the innerand outer screen 56 and 70, falls onto the periphery of vibratory screenwhich employs a central discharge opening.

By an alternative arrangement, the oversize material not passing throughthe inner and outer screen 56 and 70 may decome distributed onto thecentral area of a peripheral discharge vibratory separator. Theperiphery of a dish-shaped receiving pan (not shown) may be secured tothe lower screen support ring 70 (FIG. 10). Oversize material notpassing through the inner and outer rotating screen 56 and 70 would fallonto the dish-shaped pan (not shown) and become discharged through theopening at the center of the pan onto the central area of the vibratoryscreen. The oversize material upon the screen ultimately becomesdischarged from a peripheral discharge duct. The undersize materialpassing through the screen falls onto a dome-shaped receiving pan (notshown) disposed below the screen and becomes discharged by a dischargeduct (not shown) communicating with such pan.

As shown in FIG. 2, the entire separating arrangement is containedwithin an enclosure 43 consisting of cylindrical side walls 142, thedome-shaped top 42, and the dish-shaped bottom 143. The lower peripheralflange of the base frame 10 of the vibratory separator is bolted orotherwise secured to support struts 144 which extend between and areaffixed to the lower periphery of the cylindrical wall 142.

Undersize material which passes through the fine mesh screen 70, fallsinto the dish-shaped shell bottom 43 and is ultimately dischargedthrough the undersize discharge duct 151. Undersize material passingthrough the horizontal screen 37 of the vibratory separator which isdischarged from the discharge duct 157 may either fall to the shellbottom 43 or be separately removed from the shell by a flexible sleeve(not shown) affixed to the discharge duct 157 and communicating with adischarge pipe (not shown) affixed to the shell 43.

The sump 153 receives a portion of the undersize material passingthrough the outer screen 70. A removable screen or grating 152, afiixedto the struts 144, permits easy access to the sump for cleaningpurposes. The sump 153 communicates with the pump 154 through the pipe178. The vertical pipe 155, extending upward from the pump 154,communicates the pump 154 with the lines of the cleaning arrangement forthe rotating screens 56 and 70 by virtue of the pipe 155 communicatingwith the 1 1 coupling 156, which in turn communicates with the coupling120.

The sump 153 and pump 154 function to circulate a portion of the liquidpassing through the rotating screen 70 to the cleaning arrangement forthe vertical rotating screens 56 and 70.

It should be observed, however, that as an alternative, a fluid inletline (not shown) may enter the shell 43 and communicate with the linesof the cleaning arrangement to provide clean liquid, steam or hot fluidto the cleaning arrangement. In such a case, the sump 153 and pump 154need not be in operation.

Although the screen cleaning arrangement has been described as usingrecirculated eflluent or some extraneous fluid, the nozzles 126 for thescreen 56, the nozzles 113 for the screen 70 and the nozzles 141 for thescreen 37 may all be fed from a common fluid source. Alternatively,these screen cleaning systems may each be individually fed with aseparate source of fresh liquid, recirculated eflluent or a hot vaporsuch as steam. The entire steam cleaning system is preferably isolatedfrom the effect of the vibratory eccentric weight motor which causes thescreen 37 to vibrate during operation.

When the level of discharged material in the shell bottom 143 reaches alevel pre-set by raising or lowering the actuating float 158, the levelis maintained by the float 158 actuating a switch (not shown) which byvirtue of the cable 160 connected to the main electrical control panel(not shown) shuts off or reduces the flow of eflluent material into theinlet pipe 41.

By virtue of the cable 159 connected to the motor leads (not shown), themotor 12 of the vibratory separator may also be shut off or reduced inspeed by the switch (not shown).

The oversize material which discharges from the discharge duct 20 of thevibratory separator is ultimately discharged by way of the stationarydischarge pipe 146 which projects from the shell bottom 143. Thedischarge duct 20 communicates with the stationary discharge pipe 146through the flexible coupling 147 which isolates the vibrations impartedto the vibratory separator including the duct 20 from the stationaryduct 146.

As shown in FIGS. 1 and 3, the shell 43 which encloses the separatingdevice of this invention is provided with elongated cylindrical legs 161which vertically project from the shell bottom. The legs 161 are weldedto or fabricated as an extension of the elongated cylindrical legsupports 162. The leg supports vertically extend to a point near theupper periphery of the cylindrical shell 142 and are welded or otherwisesecured thereto. Two doors 163 conforming to the contour of thecylindrical shell 142 are secured to the shell 142 by hinges 164 at theupper and lower portion of the door. The hinges 164 are secured in asuitable manner to the elongated cylindrical leg supports 162.

Rotating door handles 165 spaced at intervals about the peripheral edgeof the opening in cylindrical shell 142 secure the doors 163 when intheir closed position. Such handles and securing means are commonlyknown in the art.

The doors 163 in their open position provide an opening in the shell 142of sufficient size to enable access to the entire separating unit forrepair or removal therefrom.

Fork lift channels 145, welded or otherwise suitable secured to the bareframe of the vibratory separator, enable a fork lift to remove thevibratory separator from the shell enclosure 43.

It is to be emphasized that the rotating screens 70 and 56 and all theirassociated mechanisms, including the distributing pans, flow dividersand feed pipes, are isolated from the vibrating cylindrical housingwhich is generally comprised of the spacing frames 19, 25, and 39, thebase 17 and vibrating eccentric motor 12.

We claim:

1. A screening apparatus comprising a substantially cylindrical screenhaving a substantially vertical axis,

means coupled with said screen for supporting and rotating said screen,

distribution means positioned adjacent said screen for feeding materialto be separated along the inner surface of said screen, saiddistribution means including a plurality of baflle members thereon forblocking a portion of the feed of said material toward the inner surfaceof said screen, and

cleaning means for spraying a fluid through said screen from the outerto the inner surface, said cleaning means including a plurality of fluidflow directing members positioned adjacent the outer surface of saidscreen and maintained substantially aligned with said baflie member ofsaid distribution means for enabling the spray of fluid to impinge uponportions of said screen from which the feed of material is blocked bysaid baflle members.

2. A screening apparatus as in claim 1 including a second substantiallycylindrical screen having a substantially vertical axis,

said means coupled with said first screen being coupled with said secondscreen for supporting and rotating said second screen,

said distribution means having a second plurality of baffle members, and

said cleaning means including a second plurality of flow directingmembers positioned adjacent the outer surface of said second screen andmaintained substantially aligned respectively with said second pluralityof baflle members.

3. A screening apparatus having means for back washing a screen memberthereof comprising a first substantially cylindrical screen having asubstantially vertical axis,

a second substantially cylindrical screen of smaller diameter than saidfirst screen mounted coaxially with respect to said first screen,

means coupled with said first and second screens for rotating saidscreens,

distribution dome means having first and second portions respectivelyadjacent said first and second means for feeding material to beseparated toward the inner sides of said screen, each of said portionsof said distribution dome means including baflle areas for preventing aportion of the flow of said material from being directed toward theinner side of said first and second screens, and

cleaning means for spraying a fluid through each of said screens fromthe outer to the inner sides thereof, said cleaning means includingfirst and second spray members, the first of said spray members beingmounted adjacent the outer side of said first screen and maintainedsubstantially aligned with the bafile areas of said first portion ofsaid distribution means, and said second spray members being mountedadjacent the outer side of said second screen and substantially alignedwith the bafile areas of said second portion of said distribution meansfor enabling spray of fluid to impinge upon the portions of saidrespective screens bafiled by said respective bafile areas.

4. An apparatus as in claim 3 including a third substantially planarscreen mounted below said first and second screens, and vibration meanscoupled with said third screen for vibrating said third screen, and

said cleaning means being isolated from said vibration means.

5. A screening apparatus comprising a substantially cylindrical screenhaving a substantially vertical axis,

means coupled with said screen for supporting and rotating said screen,

distribution means positioned adjacent said screen for feeding materialto be separated along the inner surface of said screen, saiddistribution means including a plurality of baflle members thereon forblocking a portion of the feed of said material toward the inner surfaceof said screen,

cleaning means for spraying a fluid through said screen from the outerto the inner surface, said cleaning means including a plurality of fluidflow directing members positioned adjacent the outer surface of saidscreen and maintained substantially aligned 'with said 'baflle membersof said distribution means for enabling the spray of fluid to impingeupon said screen at the areas thereof blocked by said baflle members,

a substantially planar screen mounted below said cylindrical screen suchthat material to be screened which does not flow through saidcylindrical screen is delivered to said planar screen, and

vibratory means coupled to vibrate said planar screen, said cleaningmeans being isolated from vibrations of said vibratory means.

6. A screening apparatus for screening and separating materialcomprising a substantially cylindrical screen having a substantiallyvertical axis,

means coupled with said screen for supporting said screen for rotationabout said axis,

distribution dome means positioned adjacent said screen for feedingmaterial to be separated along the inner surface of said screen, saiddistribution dome means having a plurality of segments each of whichincludes a flow divider and a material feed Surface, each feed surfaceserving to feed said material to the inner surface of said screen andeach said flow divider serving to baflle a portion of the feed of saidmaterial to areas of the inner surface of said screen, and

cleaning means for spraying a fluid through said screen from the outerto the inner surface thereof at said baflled areas thereof, saidcleaning means including a plurality of fluid flow directing memberspositioned adjacent the outer surface of said screen and maintainedsubstantially aligned with said flow dividers. 7. A screening apparatusas in claim 6 including a second substantially cylindrical screen ofsmaller diameter than said first named screen mounted coaxially withrespect to said first screen,

said distribution dome means including a second plurality of flowdividers positioned adjacent the inner surface of said second screen,and

said cleaning means including a plurality of flow directing memberspositioned adjacent the outer surface of said second screen andsubstantially aligned respectively with said second plurality of flowdividers.

8. A screening apparatus as in claim 7 including a third substantiallyplanar screen mounted below said cylindrical screens for receivingmaterial which does not flow through said cylindrical screens, and

vibratory means coupled to vibrate said third screen.

9..A screening apparatus as in claim 6 wherein said material is aliquid-solids material, said apparatus including pump means forreceiving liquid separate from said liquid-solids material, said pumpmeans being coupled with said cleaning means for supplying fluidthereto.

References Cited UNITED STATES PATENTS 811,930 2/1906 Kihl-gren 209-300X 1,134,304 4/1915 Westbye 209306 X 1,225,198 5/1917 Westby 209300 X1,450,145 3/ 1923 Ellenwood 209-311 2,975,899 3/ 1961 Cannon 209-27 3315,308 4/1885 Martin 209-304 735,444 8/1903 Baker 209-303 X 2,751,0796/1956 Aulmann 209380 X 3,221,886 12/1965 La Mort 209380 X FOREIGNPATENTS 298,602 5/1954 Switzerland.

21,562 1/1910 Norway.

HARRY B. THORNTON, Primary Examiner R. HALPER, Assistant Examiner US.Cl. X.R.

